AirSpaceMag.com

Yellow 10

SOME AIRPLANES JUST LOOK MEANER THAN OTHERS, and Yellow 10, an ultra-rare German Focke-Wulf 190D-13 fighter, is one of them. With an elongated snout housing a massive inverted V-12 engine, three 20-mm cannon, and perfect knife-like proportions, the “butcher bird,” as the Luftwaffe nicknamed it, has always looked as if it would cheerfully go for the throat of any of the other airplanes in its Arizona hangar.

During World War II, D-series 190s—called Doras—could outclimb and outrun anything the Allies put into the air, thanks to a Junkers Jumo 213 E piston engine capable of churning out 2,200 horsepower. (The P-51D Mustang’s Merlin V-12, by comparison, could muster only 1,700 hp.) Doras also featured an almost unfathomably complex mechanical “brain box” which allowed their pilots to concern themselves with only a single power lever while their Allied counterparts had to manage separate propeller, mixture, and throttle controls.

For more than two decades, visitors to the Champlin Fighter Museum in Mesa, Arizona, gawked at the dapple-gray Dora without ever realizing that the impressive showpiece was actually a gigantic jumble of mismatched parts. Those in the know had always suspected there was something wrong with Yellow 10 (the name refers to the yellow Luftwaffe squadron number stenciled on its side): The ammo chutes in its wings didn’t line up with the armament, and no one could ever quite manage to get the ailerons connected to the control stick in a logical way.

Academics speculated—but could never prove—that the U.S. Air Force was to blame. Immediately after the war, Yellow 10 and a differently armed variant were brought Stateside for testing, and it’s thought that when the fighters were crated up in the late 1940s for sale on the surplus market, their wings were accidentally switched.

The effort to correct the mismatch gained impetus two years ago, when museum owner Doug Champlin acquired the first of three demilitarized cannon to install in his Dora. “That was when we decided we either needed to make this wing work, or we needed to switch it,” remembers resident museum restorer David Goss.

After years of conversations, the Arizona team finally convinced officials at the U.S. Air Force Museum at Wright-Patterson Air Force Base in Ohio—home of the other Dora, an Fw 190D-9 on long-term loan from the Smithsonian—to swap wings with them. When the wings arrived, they fit Yellow 10 perfectly, solving the mystery of the flight control mismatches. In order for D-13s to accommodate a newly included cannon that fired through the engine and out the fighter’s signature holed spinner (earlier versions of the Fw 190 had a machine gun), German engineers were forced to route aileron control tubes further aft in the wings.

The wing switch also helped shed light on Focke-Wulf’s construction techniques. When the new wing was flayed open as part of Yellow 10’s current restoration, Goss and his crew were treated to the sound of dozens of shims—slivers of metal jammed in the structure to tighten a shoddy fit—cascading loose. Upon further examination, they also discovered hints of an odd process that may have been used to shear a stringer—a thin aluminum spar that runs along the top of the wing—from its metal stock. It’s apparent that someone bent the metal back and forth until it broke off, rather than go to the trouble of making a clean cut. The grim explanation: Yellow 10 was largely the handiwork of slaves upon whom German industry increasingly relied as the war dragged on. Seen in this light, the sloppiness takes on significance; maybe snapping off the metal was as much an act of defiance as of expediency.

Goss and Champlin feel all of this history must be preserved. Says Goss: “In 100 years, if someone decides to go looking inside this airplane, we want them to understand how things were done in Germany.”

To that end, a good deal of Goss and Champlin’s energies have gone into undoing the airplane’s first restoration, which Champlin commissioned shortly after he acquired the Dora in 1972. Although that effort, done with advice from the fighter’s designer, Kurt Tank, arrested the airplane’s deterioration, it also stripped away much of its history.

“This time around, I said, ‘Let’s do this thing right,’ ” says Champlin. That’s meant fabricating entire assemblies, such as ammo chutes and access covers for the cannon, from scratch. It has also meant replacing non-metric rivets and non-period switches and circuit breakers installed during the first restoration with originals or faithful reproductions. Champlin even paid a French company $7,000 for custom-made metric rivets for the wings. “For that amount, you could normally expect to buy enough for an entire plane,” Goss says. The team has also reinstalled the shims in the wing, but has chosen to smooth the edges of other roughly cut metal parts as a safety precaution for those who may work on Yellow 10 in the future.

While Goss steers the restoration, Champlin spends much of his time tracking down radios, instruments, and other bits of Dora minutiae. The task, he says, has been made easier by the Internet and by warbird parts discovered in the former East Germany—resources unavailable in the 1970s.

Goss and Champlin expect to be finished with the airplane early next year. Although the fighter will be perfectly flyable, Champlin says that as long as he owns it, Yellow 10 will remain earthbound. “It’s just too rare,” he says. “We’ll start it up and taxi it, but that’s all we’re gonna do. It’d just be criminal to fly it.”